Okay--I have been here, so I'm going to try to tackle this.
First of all there are a lot of different issues at hand, here.
If you don't want to be with your boyfriend, you don't want to be with him. That's very simple, and you should not feel guilty and/or as if this is somehow based on your sexual orientation. I mean, obviously if you genuinely don't want to be with him then it is for more reasons than just this, so you should just tell him. It is hard, but I think it will be a lot harder to stay in a relationship you do not want. Not to mention that you will not be being true to yourself and what YOU want.
Which brings me to the second point. Ultimately, coming out is going to mean that you are being true to what you want and what you feel despite what society says. Now, with your friends being in the "in" crowd, this may be difficult for you. But you yourself have said how superficial they can be. So--the question is whether or not coming out to them and being true to yourself is more important to you than pleasing them when you already know that they are superficial people. I'm not going to tell you what to do on this and I am not lecturing you--I am just pointing out what the real issue is there. I mean, you do not HAVE to come out to anyone, because your sexuality is your own business. But if you feel that you are living something of a lie by remaining in the closet then I think that is an important thing to think about.
As far as your parents go... well, that is a little bit hairier. For instance, your parents have a certain amount of control over you whereas you don't have to in any way let your friends or boyfriend control you (and if you did, I'd be a little worried). You may find that it would be safer to come out to them once you are financially stable--but again, if you feel that it is really important not to live a lie, and you are willing to face up to their reactions, then I think you should do what you ultimately feel is best.
I am not out to everyone--I am not out to my mother, or various people I know at school, but I HAVE come out to a good number of people who I know support me and who I can go to on the days when I wonder why it has to be that I have to hide it from other people. Generally, though, I am fine with my situation. Remember: your sexuality is your business, and whether or not you come out to your family, I think, depends a lot on if you are close to them and trust them with that information, because it is VERY personal. They certainly are not looking to you for approval of their sexual practices and I don't believe that you have to look to them for approval of the people you find attractive. However, honesty is always the best policy. In being honest at least you know you have done the right thing. If your parents have a bad reaction, that will be something you will need to deal with, but their non-acceptance of you is their problem and something which they will have to wrestle with as time goes on--because their homophobia is not right.
There are a lot of good articles and books out there on coming out, including some on this site. I'd find you some, but I've gotta run! In any case, good luck, hon, and keep us posted!
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